code: def forward(self, x):
      return paddle.reshape(
          x, x.shape[: self.start_axis] + [self.shape]
      )
  
imports: import math
  import paddle
  import paddle.nn
  import paddle.nn.functional
  from paddleclas.ppcls.arch.backbone.model_zoo.vision_transformer import VisionTransformer
label_desc: Use image node_id 2 for calling the Unflatten obj's underlying member method code with example usage: obj.forward(x) and returns: paddle